This disclosure relates to prequalification of Digital Subscriber Line (DSL), and more particularly to estimating the effect of implementing vectoring at a prequalification stage.
DSL is a technology that transmits data over a local telephone network and prequalification is a procedure to detect conditions and estimate performance of data transmission, such as bitrate, on the line.
The performance of the DSL is affected by noise such as Near-End Crosstalk (NEXT), Far-End Crosstalk (FEXT), impulse and white noise.
Vectoring is a transmission method that employs the coordination of line signals to provide cancelling and reducing of FEXT levels and improvement of performance. To implement vectoring and conditioning of the signal, extra devices need to be implemented in the Access Node (AN) located at a Central Office (CO). Vectoring requires implementation of a heavy signal processing to cancel FEXT noise.
Though vectoring cancels FEXT and greatly improves rate and reach performance, vectoring cannot achieve full improvement when there are non-vectored lines or lines form separate vector group.